Computerized process color editing apparatus is known in the art. The first such apparatus was introduced in 1979 by Scitex Corporation of Herzlia, Israel, the assignees of the present invention, under the trade name RESPONSE.
The present state of the art is represented by the Scitex RIGHTOUCH, which permits a user to select from among 16,000,000 colors.
It is clearly impossible to simultaneously display to the operator all 16,000,000 colors. Accordingly various techniques have been proposed for providing sequential interactive color choice functions in such systems.
There is described in "An Experimental Comparison of RGB, YIQ, LAB, HSV and Opponent Color Models" by Micheal W. Schwarz et al, ACM Transactions on Graphics, Vol. 6, No. 2, April, 1987 pp 123-158, a color matching experiment for interactively matching colors.
There is shown in the art various two level color selection methods. The Apple Color Manager, a software program by Apple Inc. designed for the Macintosh II, has disposed a bar with varying luminance and a two-dimensional color circle with varying hue and saturation levels where the luminance, hue and saturation levels only approximate the scientific meaning of the words. The user chooses a color from an image or from a palette of 256 colors and then corrects it by choosing a luminance level from the luminance bar and hue and saturation levels from the color circle. Upon choosing a luminance level from the luminance bar, the system displays, in a position along the luminance bar indicating the amount of luminance chosen, the resultant color as the previously chosen hue and saturation levels at the chosen luminance level. The user then chooses both hue and saturation by indicating a desired position on the color circle. The resultant color is displayed in the image.